Abstract

A compact ultrafast electron diffractometer, consisting of an s-band 1.6 cell photocathode radio-frequency gun, a multi-function changeable sample chamber, and a sensitive relativistic electron detector, was built at Shanghai Jiao Tong University. High-quality single-shot transmission electron diffraction patterns have been recorded by scattering 2.5 MeV electrons off single crystalline gold and polycrystallinealuminum samples. The high quality diffraction pattern indicates an excellent spatial resolution, with the ratio of the diffraction ring radius over the ring rms width beyond 10. The electron pulse width is estimated to be about 300 fs. The high temporal and spatial resolution may open new opportunities in various areas of sciences.

The authors are grateful to X. Wang for the leading role in the initial construction of the MeV UED facility. We thank J. Chen and Y. Chen for maintenance of the laser system, and L. Qian for support of the MeV UED project. This work was supported by the National Natural Science Foundation of China under Grant Nos. 11327902 and 11304199. J. Cao would like to acknowledge the support from Nation Science Foundation under Grant No. 1207252.

Key Topics

[Details of electrodes, of magnetic control means,
of screens, or of the mounting or spacing thereof, common to two or more basic types of
discharge tubes or lamps, Details of electrodes, of magnetic control means, of screens, or of the mounting or spacing thereof, common to two or more basic types of discharge tubes or lamps]